C++

Forum

 
 
Not Reading a Random Number

john26999 (4)
Good evening,
I am a beginner with C++ and having a bit of difficulty figuring out a small code problem with the below code. The problem is that the code is not properly identifying any of the random numbers within the 10x10 rows and columns it produces. I have analyzed the code for the last five days, re written it several times, and for whatever reason (which I fear I am too close to the problem to see it) I cannot recognize what I am apparently overlooking. So now I am putting this on the blog in hopes that some of the smarter people in the audience could look and help me figure out where I went wrong.
For transparency, yes, this was a homework assignment so please do not yell at me for putting this up. I have already submitted the broken code for a (likely) not so good grade, so that ship has sailed. I just would like to know what I could have thought of to solve the problem. This code is meant to be a random number guessing game that uses a 2-dimensional array that asks the user to guess the random number and after the number is guessed, to ask for the location within the 10 x 10 column of random numbers. I am sure all of you will identify additional problems with the code; and although I welcome any helpful pointers, I am simply requesting help with the code to simply recognize a random number within the 10 x 10 column. Thanks for the help. 

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
 
#include <iostream>
#include <cstdlib>
#include <ctime>
#include <iomanip>

using namespace std;

const int NUM_ROWS = 10;
const int NUM_COLS = 10;

//Setting values in a 10 by 10 array of random integers (1-100)
//Pre: twoDArray has been declared with row and column size of NUM_COLS
//     Must have constant integer NUM_COLS declared
//     rowSize must be less than or equal to NUM_COLS
//Post: All twoDArray has set integers 1-100
void InitArray(/*OUT*/ int twoDArray[][NUM_COLS], /*IN*/ int rowSize);

//Displays the array & set the int to constant so you cannot change it
//Pre: twoDArray contains integers with row and column size of NUM_COLS
//     Must have constant integer NUM_COLS declared
//     rowSize must be less than or equal to NUM_COLS
//Post: Display all values of array in proper format
void PrintArray( /*IN*/ const int twoDArray[][NUM_COLS], /*IN*/ int rowSize);

//Accepts an integer as a parameter and returns its first location in the array
//Pre: twoDArray contains integers with row and column size of NUM_COLS
//     MUst have constant integer NUm_cols declared
//     rowsize mus be less than or equal to NUM_COLS
//     numGuessed contains valid integer
//Post: Return ture if guessNum is in array as well as set rowLoc and colLoc coordinates
//      Return false if guessNum is not found and set rowLoc and colLoc coordinates

bool FindNumber (/*IN*/ const int twoDArray[][NUM_COLS], /*IN*/ int rowSize,
                 /*IN*/ int guessNum, /*OUT*/ int &rowLoc, /*OUT*/ int &colLoc);

int main(){

    int rowLoc = 0;
    int colLoc = 0;
    int guessNum;
    int twoDArray [NUM_ROWS] [NUM_COLS];
    int found;
    int x, y;
    //srand(time(0));
    //srand (time(nullptr)); this will get you genuine random numbers.

    InitArray(twoDArray, NUM_COLS);


    PrintArray(twoDArray, NUM_COLS);
    // Do/While loop to loop at least once and then continue to loop until the
    // number is found.
    do{
        //prompt for user to guessNum
        cout << "Please guess a number from 1 - 100 only: " << endl;
        cin >> guessNum;
        found = FindNumber (twoDArray, NUM_ROWS, guessNum, rowLoc, colLoc);
        cout << FindNumber(twoDArray, NUM_ROWS, guessNum, rowLoc, colLoc) << endl;

        //if/else statement that will check if the number was guessed correctly or not.
        if (!found) {
            cout << guessNum << "Number not found! " << endl;
        } else
            cout << "Congratulations, the number you guessed was " << guessNum << endl;

    } while (!found );

    do{
            //Prompt for location (x and y)
            cout << "Guess the coordinates of the number by row then column. " << endl;
            cin  >> x >> y;

            //test x against rowLoc and y against colLoc
              if (x == rowLoc && y == colLoc){
                cout << "Yay, you found the number. The number you guessed was "
                << guessNum << " and was located in row: " << rowLoc
                << " and in column: "<< colLoc << ". You have now graduated to a worm."
                <<"Thanks for playing. How about another game, worm? "<< endl;
                   }else if (x < rowLoc && y < colLoc) {
                        cout << "You suck!!" << "x is lower! and y is lower!"
                             << "Try again maggot!"<< endl;
                   } else if (x > rowLoc && y > colLoc){
                        cout << "You suck!!" << "x is higher! and y is higher!"
                             << "Try again maggot!"<< endl;
                   } else if (x < rowLoc && y > colLoc){
                        cout << "You suck!!" << "x is lower! and y is higher!"
                             << "Try again maggot!"<< endl;
                   } else if (x > rowLoc && y < colLoc){
                        cout << "You suck!!" << "x is higher! and y is lower!"
                             << "Try again maggot!"<< endl;
                   } else if (x == rowLoc && y > colLoc){
                        cout << "You suck!!" << "x is correct! and y is higher!"
                             << "Try again maggot!"<< endl;
                   } else if (x == rowLoc && y < colLoc){
                        cout << "You suck!!" << "x is correct! and y is higher!"
                             << "Try again maggot!"<< endl;
                   } else if (x > rowLoc && y == colLoc){
                        cout << "You suck!!" << "x is higher! and y is correct!"
                             << "Try again maggot!"<< endl;
                   }else if (x < rowLoc && y == colLoc){
                        cout << "You suck!!" << "x is lower! and y is correct!"
                             << "Try again maggot!"<< endl;
                   }

    } while (!(x == rowLoc && y == colLoc));

    //PrintArray(twoDArray, NUM_ROWS);

    return 0;
}
 void InitArray(/*OUT*/ int twoDArray[][NUM_COLS], /*IN*/ int rowSize) {

    //cout <<"init\n";
    //Loop through each row
    for (int row = 0; row < 10; row++) {
        //loop through each column
        for (int col = 0; col < 10; col++) {
            //Rand generates only one number. because it is within a four loop it generates 100 random numbers.
        twoDArray [row][col] = rand() % 100 + 1;
            //cout << twoDArray [row][col] << " ";
        }
    }
 }

 void PrintArray( /*IN*/ const int twoDArray[][NUM_COLS], /*IN*/ int rowSize) {

    //cout << "Print \n";
     //Loop through each row
    for (int row = 0; row < NUM_ROWS; row++) {
        //loop through each column
        for (int col = 0; col < NUM_COLS; col++) {
            //Rand generates only one number. because it is within a four loop it generates 100 random numbers.
            cout << setw (4) << twoDArray [row][col] << " ";
        }
        cout << endl;
    }
 }

//Accepts an integer as a parameter and returns its first location in the array
//Pre: twoDArray contains integers with row and column size of NUM_COLS
//     Must have constant integer NUm_cols declared
//     rowsize mus be less than or equal to NUM_COLS
//     numGuessed contains valid integer
//Post: Return true if guessNum is in array as well as set rowLoc and colLoc coordinates
//      Return false if guessNum is not found and set rowLoc and colLoc coordinates

bool FindNumber (/*IN*/ const int twoDArray[][NUM_COLS], /*IN*/ int rowSize,
                 /*IN*/ int guessNum, /*OUT*/ int &rowLoc, /*OUT*/ int &colLoc) {

    //loop through loops and columns and return true is found or false

        for (int rowThing = 0; rowThing < NUM_ROWS; rowThing++){
            //loop through each column
            for (int colThing = 0; colThing < NUM_COLS; colThing++)

                // check if value in array == numguessed
                 if (twoDArray [rowThing] [colThing] == guessNum ) {

                    rowLoc = rowThing +1;
                    colLoc = colThing +1;

                    return true;

       }else return false;

    }
 }
dutch (2548)
In FindNumber, the else is wrongly indented. It belongs to the if, of course, and therefore will execute the first time an array element doesn't match guessNum, returning false without having searched the whole array. Instead, the return false should be after the double loop since if the double loop completes then the number wasn't found.
Last edited on
john26999 (4)
Dutch,

Thank you for your guidance. Your solution worked. I kept the else statement where it was and moved the return false statement after the double loop. Now the code works fine.
Last edited on
Topic archived. No new replies allowed.